<?php
/**
 * 2007-2017 PrestaShop
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/osl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@prestashop.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade PrestaShop to newer
 * versions in the future. If you wish to customize PrestaShop for your
 * needs please refer to http://www.prestashop.com for more information.
 *
 * @author    PrestaShop SA <contact@prestashop.com>
 * @copyright 2007-2017 PrestaShop SA
 * @license   http://opensource.org/licenses/osl-3.0.php Open Software License (OSL 3.0)
 * International Registered Trademark & Property of PrestaShop SA
 */

/**
 * Removes duplicates from table category_group caused by a bug in category importing in PS < 1.4.2
 */
function remove_duplicate_category_groups()
{
    $result = Db::getInstance()->executeS('
		SELECT `id_category`, `id_group`, COUNT(*) as `count`
		FROM `'._DB_PREFIX_.'category_group`
		GROUP BY `id_category`, `id_group`
		ORDER BY `count` DESC');
    
    foreach ($result as $row) {
        if ((int)$row['count'] > 1) {
            $limit = (int)$row['count'] - 1;
            $result = Db::getInstance()->execute('
				DELETE FROM `'._DB_PREFIX_.'category_group`
				WHERE `id_category` = '.$row['id_category'].' AND `id_group` = '.$row['id_group'].'
				LIMIT '.$limit);
        } else {
            return;
        }
    }
}
